Chapter 3

Base Pairs

A pairs with T, and C pairs with G, producing _______.

Gene

A particular nucleotide sequence that can instruct the formation of a polypeptide is called a ____.

Functional Group

Affects a biological molecule's function in a characteristic way.

enzymes

All biological reactions of this sort are mediated by _____, which speed up chemical reactions in cells. Proteins that serve as metabolic catalysts, regulate the chemical reactions within cells.

1. the size and shape of the molecule 2. the groups of atoms attached to it

An organic compound has unique properties that depend upon

Isomers

Carbon skeletons can be branched or unbranched. Therefore, different compounds with the same molecular formula can be produced. These structures are called

Hydrophilic

Compounds containing functional groups are called ______. This means that they are soluble in water, which is a necessary prerequisite for their roles in water based life.

Linus Pauling

Contributed to our understanding of the chemistry of life. After winning a Nobel Prize in Chemistry, _____ spent considerable time studying biological molecules. He discovered an oxygen attachment to hemoglobin as well as the cause of sickle-cell disease. He also discovered the alpha helix and pleated sheet of proteins.

Nucleotides

DNA and RNA are composed of monomers called _____. They have three parts.

Unsaturated Fats

Fats (compounds) that have fewer than the maximum number of hydrogens

Denaturation

If for some reason a protein's shape is altered, it can no longer function. ________ will cause polypeptide chains to unravel and lose their shape and thus their function.

Hydrocarbons

Methane and other compounds composed of only carbon and hydrogen are called

dehydration reactions

Monomers are linked together to form polymers through _______, which remove water.

Polysaccharides

Monosaccharides can be hooked together to form _______. They are polymers of monosaccharides.

hydrolysis

Polymers are broken apart by _______, the addition of water.

Amino Acids

Proteins are made from _____. They are the building blocks of proteins, and they have an amino group and a carboxyl group.

Primary structure

The ______ of a protein is its unique amino acid sequence. The correct amino acid sequence is determined by the cell's genetic information.

Secondary structure

The ______ of a protein results from coiling or folding of the polypeptide.Coiling results in a helical structure called an alpha helix. Folding may lead to a structure called a pleated sheet.

macromolecules polymers monomers

The four classes of biological molecules contain very large molecules. They are often called ______ because of their large size. They are also called ______ because they are made form identical building blocks strung together. The building blocks are called ______.

Tertiary Structure

The overall three-dimensional shape of a protein is called its ______. Generally results from interactions between the R groups of the various amino acids. Disulfide bridges are covalent bonds that further strengthen the protein's shape.

Disaccharide

Two monosaccharides (monomers) can bond to form a _______ in a dehydration reaction.

Quaternary structure

Two or more polypeptide chains (subunits) associate providing ______. Collagen is an example of a protein with ______. Its triple helix gives great strength to connective tissue, bone, tendons, and ligaments.

Double Helix

Two polynucleotide strands wrap around each other to form a DNA ______

Adenine, Thymine, Cytosine, and Guanine

What are the DNA nitrogenous bases?

Adenine, Uracil, Cytosine, guanine

What are the RNA nitrogenous bases?

1. carbohydrates 2. proteins 3. lipids 4. nucleic acids

What are the four classes of biological molecules?

1. primary structure 2. secondary structure 3. tertiary structure 4. quaternary structure

What are the four levels of protein structure?

1. Hydroxyl group 2. Carbonyl group 3. Carboxyl group 4. Amino group 5. Phosphate group

What are the functional groups?

1. A five-carbon sugar called ribose in RNA and deoxyribose in DNA 2. a phosphate group 3. a nitrogenous base

What are the three parts of Nucleotides?

Monosaccharides

______ are the simplest carbohydrates. Sugar monomers are _______, such as glucose and fructose.

Carbonyl group

a carbon linked by a double bond to an oxygen atom

carbon skeleton

a chain of carbon atoms is called a

Protein

a polymer built from various combinations of 20 amino acid monomers.

Cellulose

a polymer of glucose that forms plant cell walls.

Chitin

a polysaccharide used by insects and crustaceans to build an exoskeleton

Starch

a storage polysaccharide composed of glucose monomers and found in plants.

Glycogen

a storage polysaccharide composed of glucose, which is hydrolyzed by animals when glucose is needed.

Lipids

are water insoluble (water fearing, hydrophobic) compounds that are important in energy storage.

Organic Compounds

carbon-based molecules are called

Amino group

composed of a nitrogen bonded to two hydrogen atoms and the carbon skeleton

Carboxyl group

consists of a carbon double-bonded to both an oxygen and a hydroxyl group

Hydroxyl Group

consists of a hydrogen bonded to an oxygen

Phosphate group

consists of a phosphorus atom bonded to four oxygen atoms

Saturated fats

fats (compounds) with the maximum number of hydrogens

Signal proteins

proteins that are best exemplified by the hormones

Contractile Proteins

proteins that are found within muscle

Transport proteins

proteins that carry oxygen

Defensive proteins

proteins that include antibodies of the immune system

Structural Proteins

proteins that provide associations between body parts

Receptor Proteins

proteins that serve as antenna for outside signals

Anabolic Steroids

synthetic variants of testosterone that can cause a buildup of muscle and bone mass.